The true wasted potential

After jjk ended horribly last year, many people made videos about the wasted potential of jjk, but the true wasted potential, was aot, and I know people have been talking about the ending and all of that, but no one talks about it in terms of wasted potential, whether it's some plot points that were nelgected, some questions that weren't answered, or anything along these lines, so what would you say aot exceeds in, and had immense potential, that could've elevated the story even more, but ended up not delivered/neglected or forgotten?